Tim,
>From EN55022:2006 +A1: 2007
Section 9.5.2 Tabletop equipment arrangement
2) "...........(for example on an open area test site (OATS) or in a screened
enclosure). The EUT shall be placed on a non-conductive table such that it is
0,4m above the horizontal ground reference plane."
Regards,
David Spencer
EMC Engineer
Xerox Corp.
________________________________
From: [email protected] [mailto:[email protected]] On Behalf Of Wan
Juang Foo
Sent: Wednesday, September 23, 2009 1:46 AM
To: [email protected]; [email protected]
Cc: Wan Juang Foo
Subject: Re: Conducted emission measurements
Hello Tim,
I may be missing. Is there such a 40 cm height? Here is my 5 ยข worth.
These are some of the the special provision for conducted emission
testing:
To meet EN 55011, I suppose since 1999?? the measurement may be
carried out:
- on the radiated emission test site (same EUT
configuration)
- above a metal ground plane which shall extend at least
50 cm beyond the boundary of the equipment under test
and have a minimum size of 2m x 2m
- within a screened room; either the floor or one wall
of
the screened room shall act as the vertical ground plane
.. CISPR 22 since (1993) and Amendment 1 (1995)
Table- top EUTis to be placed 40 cm from a vertical
metal reference plane
(e.g. a wall of a screened room/enclosure)
"The EUT, where intended for table-top use, shall be
placed 0,4 m from a
vertical metal reference plane of at least 2 m by 2 m and shall be kept at
least 0,8 m from any other metal surface or other ground-plane not being part
of the EUT. If the measurement. is made in a screened enclosure, the distance
of 0,4 m may be referred to one of the walls of the enclosure."
Floor- standing EUT on a horizontal metal ground-
plane, not in metallic
contact with the ground- plane. Metal floor of a screened room may replace the
reference ground- plane
best regards,
Tim Foo
Expert Witness, EMC and Product Safety
ECE, School of Engineering,
http://www.np.edu.sg/ece/ DID: +65 6460 6143
Ngee Ann Polytechnic,
535 Clementi Road, Fax: +65 6467 1730
Singapore 599489
[email protected] wrote on 23/09/2009 06:06:05 AM:
> Hello Group,
>
> I have a question about the conducted emission measurements
> performed in a semi-anechoic chamber.
>
> CISPR 22 requires the use of a vertical ground plane when testing
> tabletop EUTs, unless you mount your EUT on a non-conductive table
> 40cm above the horizontal ground plane (instead of the traditional
80cm)
>
> I did not find a requirement for a vertical ground plane when
> testing floorstanding equipment. If one opts to use the alternative
> method of not using the vertical ground plane, can floorstanding
> equipment also be tested without the vertical ground plane? The
> horizontal ground plane is always present since that is the chamber
floor.
>
> What are most labs using? We have the option of making a removable
> vertical ground plane "wall" or mounting the equipment on a 40cm
table.
>
> Thanks,
> Tim Pierce
> -
________________________________
NOTICE:
This message may contain privileged/confidential information. If you
are not
the intended recipient of this email, please delete it immediately and notify
the sender .
-
This message is from the IEEE Product Safety Engineering Society emc-pstc
discussion list. To post a message to the list, send your e-mail to
<[email protected]>
All emc-pstc postings are archived and searchable on the web at
http://www.ieeecommunities.org/emc-pstc
Graphics (in well-used formats), large files, etc. can be posted to that URL.
Website: http://www.ieee-pses.org/
Instructions: http://listserv.ieee.org/request/user-guide.html
List rules: http://www.ieee-pses.org/listrules.html
For help, send mail to the list administrators:
Scott Douglas <[email protected]>
Mike Cantwell <[email protected]>
For policy questions, send mail to:
Jim Bacher <[email protected]>
David Heald <[email protected]>
